Various type of athlete headgear having an attached device that performs some type of monitoring is known in the art.
Application US 20120210498 discloses a headgear sensor, an impact sensor and a device to measure the correct location of headgear on an athlete.
U.S. Pat. No. 4,303,241 describes a vision interrupting device which interrupts a player's vision of the ball so that the player can observe the trajectory of the ball for only a predetermined time after it is released.
U.S. Pat. No. 8,568,256 discloses an apparatus which helps provide contrasting colors to help one recognize the spin of a baseball.
U.S. Pat. No. 8,062,037 describes visual identifiers during game play and training exercises to improve vision, focus, and concentration including an American football having unique visual identifiers for use as an in-flight visual training tool.